# Crossing Angles of Geometric Graphs

• Karin Arikushi
• Csaba D. Tóth
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7402)

## Abstract

We study the crossing angles of geometric graphs in the plane. We introduce the crossing angle number of a graph G, denoted can(G), which is the minimum number of angles between crossing edges in a straight line drawing of G. We show that an n-vertex graph G with can(G) = O(1) has O(n) edges, but there are graphs G with bounded degree and arbitrarily large can(G). We also initiate studying the global crossing-angle rigidity of geometric graphs. We construct bounded degree graphs G = (V,E) such that for any two straight-line drawings of G with the same prescribed crossing angles, there is a subset V′ ⊂ V of |V′| ≥ |V|/2 vertices that are similar in the two drawings.

## Keywords

Complete Graph Supporting Line Geometric Graph Free Vertex Geometric Thickness
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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## Authors and Affiliations

• Karin Arikushi
• 1
• Csaba D. Tóth
• 1
1. 1.Department of Mathematics and StatisticsUniversity of CalgaryCalgaryCanada